Zone Builder is a new map editor designed specifically for SRB2. While there have been map editors for SRB2 before, they're all outdated, buggy and abandoned by now - making you jump through hoops to get things done. Hopefully, this stops today. Zone Builder is based on the actively developed GZDoom Builder editor (itself a comprehensive update of Doom Builder 2), and with significant care put into its development even before the first release, the intent is to make sure you never want to reach for another level editor again.

Features inherited from Doom Builder 2/GZDoom Builder
If you haven't used Doom Builder 2 or GZDoom Builder before, here are a few of the features that will be new to you:

Unlike in the old (SRB2) Doom Builder, level geometry will rarely if ever break if you copypaste it around or draw linedefs through existing geometry. New vertices will be added and sector references corrected so that everything stays intact.

In the regular 2D view, the floor textures of the sectors are overlaid over the map (you can also change this to show the ceiling textures or the brightness levels instead). Likewise, the real sprites of the Things in the map are shown.

When you hover over a control linedef or its tagged sector, an arrow will show up that shows their connection. In Sectors Mode, the sector tags are also shown inside the sectors.

There are several drawing modes that allow you to easily draw generic shapes like rectangles, curves and circles.

When creating a new linedef, its length and angle will always be visible on screen - so you don't have to play around with your viewpoint to get the whole picture.

You can have Things selected together with other level geometry at the same time. Just switch to another editing mode after making your selection and it will still be active. You can then move, resize, rotate and flip these selections all at once by pressing E to open Edit Selection Mode. Pressing C clears your selection.

There's a Nodes Viewer mode that allows you to view the data generated by the nodebuilder (pretty useless, but cool to play around with).

SRB2-specific features
A lot of effort has been put into 3D mode – so let's list the SRB2 features which now work in it as they do in-game (features in bold have never been handled properly in a SRB2 map editor before, and those that have are handled with significantly more polish):

Colormaps(incomplete: currently rendered at full intensity regardless of the specified alpha value)

Skies are rendered in 3D mode

Outside of 3D mode, notable features include the addition of a Flags Value field for all Things, so you don't have to go counting up the checkboxes and multiply the Z value by 16 each time you want to do something with a nonstandard use of flags, as well as a field for displaying and editing the Parameter value of a Thing, for the few Thing types that use it.

As you may remember, SRB2 Doom Builder had the ability to rename the Ambush flag for Thing types where it has a special significance, i.e. displaying "Float" instead of "Ambush" for rings. Workbench expanded that to the Special flag. Zone Builder is the first editor where every relevant Thing and linedef property can be renamed, including all flags, the flags value field and the Angle field. Hopefully this will make it easier to set up special effects without having to look up which field does what on the Wiki all the time.

For the few members of our community who also enjoy modding Doom and its many source ports, Zone Builder is almost* a functional superset of GZDoom Builder and as such comes packaged with all of the default Doom, Chex Quest, Strife and Hexen configuration files to map with to your heart's content (disabled by default, though, because we know what most of you are here for – if you really want to play, go delving into the Game Configurations menu in Tools).

*The editor does not have any SRB2-specific behavior when working on Doom maps, but there was one feature removal for all map types. Rest in pieces, "Bridge Mode". You shall not be missed.

Releases

16/12/2018 - v2.9 - SRB2Kart config and PK3 support

Spoiler: Changelog

Added feature: Added the configuration file for SRB2Kart. It's enabled by default in new installations, but if you updated an existing installation, you have to enable it manually under Tools -> Game Configurations.

Changed behavior: The PK3 reader now looks for SOCs in the "SOC" folder rather than "SOCs", just like SRB2.

Added feature: Added an option to draw Things at a fixed size in the 2D view, rather than scaling them with the zoom level.

Added feature: Some additions to the config.

03/12/2017 - v2.8 - Two bugfixes

Spoiler: Changelog

Bugfix: Linedef flag settings are no longer lost when copypasting linedefs.

Bugfix: Fixed a crash in the Tag Statistics window if you remove a tag label.

03/11/2017 - v2.7 - A bunch of stuff that has been sitting around for way too long

Added feature: Colormaps and FOFs with tag 65535 (global) are now displayed in Visual Mode.

Added feature: PK3s are now supported. ZB looks for patches in the directories "patches", "textures", "flats", "sprites" and "graphics". It also reads custom Thing definitions from SOCs (in the "socs" directory) and Lua scripts (in the "lua" directory). Right now PK3 support is irrelevant for you, dear v2.1 user, but come v2.2 this will be quite useful.

Added feature: You can now specify a category for custom Things with the $Category keyword. It works just like $Name and $Sprite.

Changed behavior: The custom Thing definition parser no longer throws an error when it can't read a single value. Instead, it throws a warning and continues parsing the rest of the file.

Added feature: The custom Thing definition parser can now read addition in a very limited manner, so stuff like "16*FRACUNIT + 32768" will no longer throw an error.

Added feature: The custom Thing definition parser now recognizes the flags MF_SOLID and MF_SPAWNCEILING. In particular, this means that Things with the MF_SPAWNCEILING flag are now displayed properly in 3D mode.

Added feature: Added a nodebuilder configuration for normal ZenNode without REJECT. This might be useful for test builds on very large and complex maps, where ZenNode's fast setting produces errors.

Bugfix: ZWADs are now rejected with an error message instead of crashing the program.

Added feature: Added an option to disable the crosshair in 2D view.

Bugfix: Fixed a bunch of typos in the config.

Changed behavior: Changed the names of a few specials in the config that were bothering me. For example, monitors are now listed under "Monitors" instead of "Item boxes".

28/01/2017 - v2.6 - SRB2 Top Down config and bugfixes

Spoiler: Changelog

Added feature: Added the configuration file for SRB2 Top Down. It's enabled by default in new installations, but if you updated an existing installation, you have to enable it manually under Tools -> Game Configurations.

Bugfix: When changing the offsets of a linedef with a repeating middle texture (either manually or with the auto-alignment tool), the multiples of 4096 that control how often the texture is repeated are no longer cut off.

Bugfix: ZB no longer crashes if the loaded files contain multiple SOC/Lua lumps with the same name - it simply ignores all duplicates and prints a warning in the console.

Bugfix: "Slope backside" linedef types with the No Knuckles flag now use the offsets of the back sidedef as they should, instead of the front sidedef.

Bugfix: Thing angles outside of 0-359 are now recognized in Find/Replace mode.

Bugfix: The ROIH and ROII versions of the Bustable Block Sprite Parameter sector types are no longer mixed up.

17/09/2016 - v2.5 - Updates for 2.1.16 and bugfixes

Spoiler: Changelog

Added feature: Various minor updates for 2.1.16, such as updating the Lua syntax highlighting and adding new slope-related linedef types and flags to the config.

Changed behavior: Adapted the pegging behavior for lower textures with the Lower Unpegged flag, which was changed in 2.1.15.

Bugfix: Fixed two issues with the Lua parser's $Name parameter: Spaces are now accepted in the name and there's no longer a ] at the end of every name.

Bugfix: Fixed some issues with the skewing of upper textures on slopes.

Bugfix: Colormap is now applied correctly to flipped Things.

Bugfix: Indefinitely tiled middle textures with a vertical offset are now displayed correctly in 3D mode.

Bugfix: Fixed a crash when creating a custom FOF with an invalid back upper texture.

Bugfix: Fixed a crash when opening the edit window for a linedef with action 402 (aka the weirdest bug ever).

Bugfix: Fixed some description errors with linedef type 414 in the config.

Bugfix: Fixed several crashes in the Choose Thing Type window that happened when pressing certain keys while no Thing is selected.

Bugfix: Thing angles outside of 0-359 are now preserved when copypasting or placing new Things.

Bugfix: The BLOCKMAP and REJECT lumps are now deleted before nodebuilding to prevent outdated data from being loaded in-game and messing everything up.

24/05/2016 - v2.4 - Updates for 2.1.15

Spoiler: Changelog

Added feature: Various minor updates for 2.1.15, such as updating the Lua/SOC syntax highlighting and removing the "+ Slopes" from the config name

Added feature: Colormap rendering can now be disabled in Visual Mode by pressing Alt+C.

Added feature: You can now supply a name to be displayed in the editor for custom Things. This is done with the $Name parameter; the syntax is the same as for $Sprite.

Added feature: Updated the codebase to revision 2501 of GZDoom Builder, so now I'm only 135 revisions behind instead of 144. :X

Added feature: The script editor now supports Lua and SOC scripts, with syntax highlighting and autocompletion. It will automatically open tabs for all SOC_ and LUA_ lumps in the currently loaded file, as well as for the MAINCFG and OBJCTCFG lumps (even if they don't exist yet). You can also create and edit standalone SOC and Lua files, but you can't add new script lumps to existing WADs (except for MAINCFG and OBJCTCFG in the currently loaded file), because Zone Builder isn't a lump editor and I don't plan for it to become one.

Added feature: Zone Builder now automatically searches all Lua and SOC scripts in the currently loaded files for custom Thing definitions. These custom Things are then recognized by the editor and added to the list of Things. You can set the sprite that the editor displays for a custom Thing with a special comment; look here for an explanation.

Added feature: You can now assign shortcuts for increasing/decreasing the number of Things and the radius in Insert Things Radially Mode. If you're updating from a previous version, you may have to set the shortcuts yourself, otherwise the default values are Ctrl+ScrollUp/ScrollDown for Increase/Decrease Number of Things and Shift+ScrollUp/ScrollDown for Increase/Decrease Radius.

Bugfix: When testing a map, the temp file that contains potentially unsaved changes is no longer loaded if it's identical to an already loaded file. This was changed because SRB2 is stupid and refuses to start if it loads two identical files.

Bugfix: Fixed a bug that caused offsets to be incorrectly applied to middle textures.

Added feature: The Parameter property of Thing types is now recognized and can be edited in the Thing edit form. Things with the same type but a different parameter value are now recognized as having the same type.

Added feature: Added Insert Things Radially Mode, which allows you to place a circle of Things in the map (useful for NiGHTS mapping).

Changed behavior: When testing a map with unsaved changes, the game now loads the unsaved changes as well. If you have already set up a testing configuration, you will have to edit it for this to work: In the Testing tab of the Game Configurations window, check the "Customize parameters" box. In the Parameters field, add "%F" (with quotes) after -file "%AP".

Changed behavior: Disabled the Visplane Explorer by default since it's useless for SRB2 and prone to crashes. You can re-enable it under Game Configurations -> Modes if you like crashes.

01/02/2016 - v2.1 - Bugfixes

Spoiler: Changelog

Bugfix: Creating and copypasting certain FOF control linedefs no longer crashes the editor.

Bugfix: The nodebuilder is no longer invoked twice when entering 3D mode.

Bugfix: Due to an oversight, the nodebuilder was called with the "Save" settings rather than the "Test" settings when entering 3D mode, which took much longer. This is now fixed.

Bugfix: Entering 3D mode in a map with invalid nodebuilder data (for example a map with only one sector) no longer crashes the editor.

Added feature: In the Testing tab of the Game Configurations menu, the skill level option has been replaced with skin and gametype option for SRB2 configurations.

Added feature: Updated the codebase to revision 2492 of GZDoom Builder. Besides skies, the most notable addition on the GZDB side is that Find/Replace mode now allows you to search for floor and ceiling flats.

Changed behaviour: The minimum segment length for the Draw Curve tool is now 1.

Changed behaviour: Changed the "About Zone Builder" icon.

Changed behaviour: Changed the uninstaller icon.

Changed behaviour: Visplane Explorer is now available for SRB2 maps.

Changed behaviour: "Copy Properties" tool is now available for SRB2 maps.

Changed behaviour: The default texture for SRB2 maps is now "GFZROCK", the default flats are "GFZFLR01" and "F_SKY1".

Changed behaviour: Updated the default flag names for Effects 1-5 to reflect their usage in the Public Next SRB2 repository.

Bugfix: Prevented negative Thing heights for SRB2 maps (rollover led to them being extremely far off the ground in-game despite rendering properly in the editor).

Bugfix: Raised maximum number of segs from 32767 (signed 16-bit) to 65535 (unsigned 16-bit), like it is in SRB2 (as a result, large maps no longer crash Visual Mode).

Bugfix: Lumps in the same WAD file are not autocapitalised when saving a map (for those of you who want to recreate 1.09.4 and bundle terrible characters with your level packs).

Added feature: The number of maximum backup files is now configurable under Preferences -> Interface.

Changed behavior: Slope vertices are now rendered so that their center intersects with the slope, rather than the bottom.

Changed behavior: The selection isn't automatically cleared anymore in Visual Mode by default. You can re-enable this setting under Preferences -> Editing.

Changed behavior: Linedef angles are now displayed like in SRB2 (0 degrees means the linedef goes from west to east).

Bugfix: Vertex slopes are now always displayed correctly in Visual Mode. Unfortunately, this means that the nodebuilder is now run every time you enter Visual Mode with unsaved changes. It normally shouldn't take more than a few seconds even on large maps, but if you have issues with it, go to Preferences -> Editing and check "Use blockmap instead of nodes in Visual Mode". Note that this may cause some vertex-based slopes to be displayed incorrectly.

Installing Zone Builder
Just download the installer in the attachment below and run it. It will take care of all the necessary dependencies. On the off chance that something goes wrong, here's what you need:

After installing, you need to point Zone Builder to SRB2's IWAD and executable. For that, go to Tools -> Game Configurations in the menu bar and select "Sonic Robo Blast 2 - 2.1". In the Resources tab, click Add resource... and the folder symbol in the window that pops up to select the IWAD. Navigate to your SRB2 folder and select "srb2.srb". Then, in the Testing tab, select SRB2 as your application. After that, you're good to go!

If you have trouble mapping with this editor, have a look at the Zone Builder tutorial on the Wiki, which explains the basics of mapping with Zone Builder. If you want to keep up with development, look at which new features are currently prioritized or just want to see the source code for yourself, here's where you'll find the Git repository and issue tracker.

If you have any further questions, please ask in #srb2fun or as a reply to this thread. Happy mapping!

Woop, i seem to have found a bug, you can't keep your selection in 3D Mode, once you move your Mouse to another surface your Previous selectiong unselects itself (Not sure if it only happens for floors and ceilings) .